Adams/CAR Simulation Error

[AndyZ88]

Hello,
I've been playing around with the Template Builder, modeling a rear MacPherson-style suspension with 2 lower transversal arm and an aditional trailing arm. As far as I can tell, I have specified correctly all the parts, links, joints, bushings, in/out communicators (except suspension parameters array, details further down).

However, when I try to run an analysis, like parallel wheel bump, I get this error:

command: FILE/COMMAND=baseline_parallel_travel.acf
command:
command: file/model=baseline_parallel_travel

ERROR: The MARKER referenced by ID number does not exist.
ERROR: Value : 127
ERROR: Argument : J
ERROR: Statement : JOINT/49
ERROR: Line number : 2944

ERROR: The MARKER referenced by ID number does not exist.
ERROR: Value : 132
ERROR: Argument : J
ERROR: Statement : JOINT/50
ERROR: Line number : 2950
ERROR: Errors in the Adams dataset prevent it from being loaded into the database.


---- START: ERROR ----
Attempt to read in model into AMD was unsuccessful

---- END: ERROR ----

Where can I check too see which are the markers or joints with problems?
The unclear part in the Template Builder was setting up the "suspension parameters ARRAY", I think this is the thing that's causing the error. From my understating, this array is mandatory, it must establish the steering axis in order to give out results in simulation. I'm not really sure how to set it up though. For now, I have selected "Instant Axis", the knuckle/upright part and the coordinates of the wheel centre.

I have attached a picture with the geometry of the knuckle/upright and the arms attached to it, can you please help me figure out the settings for the array & steering axis?

 

[GregLocock]

No, that error says that the model hasn't built correctly. Sadly I can't tell much more than that.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[AndyZ88]

Is there some way I can pinpoint the joints or markers with problems? Some file generated somewhere? (I'm working in the default acar database & default folder, if that helps)

 

[GregLocock]

Sure, export the model as an .adm file, then import it into ADAMS/View, and use the graphical database navigator to figure out your connectivity issue. or else read the adm directly, which'll put hairs on your chest

Solver is telling you that markers 127 and 132 have not been defined, which in the adm are statements that look like this


MARKER/5310,PART=051 P10 LF CONTACT PATCH CENTER
, QP=1790.0,-754.13,194.97

This tells the solver that it has a marker attached to part 51, at a certain location

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[AndyZ88]

Thank you, I will give it a try

 

[AndyZ88]

Okay, so I checked the .adm file using Notepad.
Marker 127 corresponds to the connection between left knuckle and front left lower control arm. It's weird that the connection on the right side, which is symmetrical and was created automatically, does not show an error... Anyway I deleted it and remade it.

Marker 132 has an Adams view name "kp2_1", also on the left knuckle. I assume the other part has the connection set as "kp1_2", correct? If so, in this case the other part is the right upper strut. The joint between the knuckle and upper strut is cylindrical, why does it appear as "kp...." ?

===

The weird part is that I saved the model with another name (after making the joint modifications), and I made another subsystem and suspension assembly with the new template name. It still gives an error on markers 127 and 132, but this time when I open the .adm file, marker 127 has the details of the old marker 126, which was OK before.

 

[GregLocock]

First of all, download Beyond Compare or an equivalent. Unfortunatley that's about the end of the advice, I think you need to speak to MSC support

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[AndyZ88]

Thank you for your help, I'll figure it out eventually. Or just remake the whole template, it's good practice anyway.

 

[GregLocock]

Yes, making templates is non trivial, I usually end up doing almost anything to avoid it unless it is for a production car, in which case the options these days don't vary much.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?